The present invention relates to methods and a system for the automatic detection of parking zones on at least one street.
With the increasing number of vehicles in a confined space, parking information is becoming increasingly important. In the past, manual counts of parking spots were taken and the position of said parking spots was recorded. Construction measures mean that the number of parking spots and the position thereof is continually changing, however.
Modern automobiles already have ultrasonic sensors and cameras installed that are capable of surveying parking spots or parking spaces and in this way of allowing automatic parking, for example. A method already known from DE 10 2012 201 472 A1 takes the vehicle internal camera images as a basis for detecting parking spots and free parking spaces.
The previous system has considerable disadvantages, however. In order to record the parking spot situation in a region, it is necessary to travel along every road in this region at least once. In this case, the roads are traveled along at different rates. Complete coverage of a region is not influenceable and lengthy. The camera images are highly dependent on where the vehicles travel on the road (e.g. distance from the curb) and what the lighting is like. In addition, it is often only possible to register the right hand side of the road. The vehicle-based method is further very computation time intensive.
It is therefore an object of the present invention to overcome the known disadvantages and to provide a method and a system that permits ascertainment of parking zones on at least one street.
The subject of the present invention is a method for the automatic detection of parking zones on at least one street, in which    a) a computing unit is provided,    b) information in the form of panorama images of the at least one street is read in from an external data memory,    c) information in the form of road data for the at least one street is read in from a map database,    d) an internal database is produced that persists the panorama images,    e) the panorama images read in are analyzed for the presence of vehicles,    f) the panorama images read in are analyzed for the presence of road signs and traffic signs,    g) the analyses of the presence of vehicles and the presence of road signs and traffic signs are used to determine, for at least one selected street, no-existing parking/no-stopping zones that are to be expected,    h) a data record is produced and stored that contains the determined information pertaining to detected vehicles and road signs and also the markings for no-parking/no-stopping zones and parking zones, and    i) the information contained in the data record is visualized on a terminal.
One preference according to the invention is a method in which the panorama images read in in step b) are satellite photographs or images of the at least one street that are produced by camera movements.
One preference is also a method in which the panorama images comprise information pertaining to the geoposition of the panorama image, the direction of travel, the road name and/or pertaining to the depth map, wherein the information is historic data.
A further preference is a method in which the road data read in in step c) comprise information pertaining to road lanes and/or pertaining to the road type.
A particular preference according to the invention is a method in which the information in the form of panorama images and road data is transmitted by way of an interface of the computing unit that is communicatively connected to the internal database and/or to an external data memory and/or to a map database.
One preference according to the invention is also a method, wherein in step e) the analysis of the vehicle detection is performed by way of segmentation of the panorama images.
An additional preference is a method, wherein in step f) the analysis of the traffic signs and road signs is performed by way of the recognition of the shape and coloration of the road signs.
One preference in this case is a method in which the analysis is performed by using image recognition software.
One preference according to the invention is also a method, wherein in step i) the information contained in the data record is visualized by virtue of said information being depicted on a separate display of a terminal.
The method has at least the following segments.
Read in of Satellite Images
In order to go over a city or a region in automated fashion completely, there is the option of evaluating panorama images in automated fashion. In one preferred embodiment, this is accomplished by extracting data from Google Street View. There, it is possible to obtain panorama images produced by Google containing information pertaining to the position of the image, direction of travel, road name and depth map. The system allows a subregion to be selected in a map, such as Google Street View, for example. Based on this, the adjoining roads are gone through from image to image by calling up the Google Street View API.
Integration of Map Data
Map data provide the number of lanes on a road and the type of said road. On this basis, the necessary zoom level or the angle of the camera images can be set. In addition, the map data provide support for the validation—for example where a road belongs to a road category in which it is not permitted to park.
Performance of Vehicle Detection
The method used is based on computer vision methods. It consists of the following steps:    Segmentation of Images    Classification of components such as vehicle or road.    Counting of the vehicles on the basis of the size of images, position in the image, etc.
Since a learning method is involved, a volume of data comprising labeled images is required as training.
Performance of Sign Recognition
Two methods are used for recognizing signs. One method recognizes shapes while the other method specifically evaluates the coloration of the images. Ultimately, the intersection of the recognized signs is used. In this case too, it is again necessary to use training data for the learning of the method.
Fusion of the Detected Signs and Vehicles
The production of parking data requires parking areas and no stopping zones to be detected. Although it is possible to infer valid parking areas on the basis of the detected vehicles, incorrectly parked vehicles mean that this is not reliable information. On the other hand, the “nonexistence” of vehicles does not allow a no stopping zone to be inferred either. For this reason, the information about detected vehicles is fused with detected sign positions. In one preferred embodiment, this involves the number of vehicles being analyzed around a detected sign. If said number is below a specific percentage/surface area, then a no stopping zone is detected.
Visualization and Style of Result
The system allows both visualization of the detected vehicles and signs and the marking of no stopping and parking zones. Further, a system is provided that goes over roads in panorama images in automated fashion and performs detection of parking vehicles and parking zones.
For visualization purposes, it is particularly possible for KML files to be used. KML is the abbreviation for keyhole markup language and is a markup language for geodata. Such files are suitable for the superimposition of and for combination with geographical maps of all kinds. The results and data records determined according to the invention from the image recognition modules can be converted into KML files and thus visualized together with other map data.
The present invention additionally provides a computer program product that is loadable directly into an internal memory of a computing unit and comprises software code or portions thereof that are executable for the purpose of carrying out the method steps according to the invention when the computer program product is executed on a computing unit.
Finally, the present invention provides a system for the automatic detection of parking zones on at least one street, comprising    a) at least one computing unit,    b) at least one external data memory with panorama images,    c) at least one map database with road data,    d) at least one internal database,    e) at least one piece of image recognition software for analyzing the existing vehicles and the existing no stopping signs and traffic signs, and    f) at least one terminal for visualizing information.
The system according to the invention therefore has the following components: interface(s) to provider(s) of panorama images and extraction of images in the chosen area; interface(s) to the map database in order to evaluate road data; database and design thereof in order to persist image data and attributes; interface to the image recognition software (vehicle detection); interface to the image recognition software (sign detection); module for fusing the results of the detections and module for visualizing the results and storing the data.
The present invention and the method provided thereby and also the system and the computer program product have a series of advantages. Using the system according to the invention, the method according to the invention can be used to initialize or map the parking situation in a city or a new region in automated fashion and to make a statement about available parking zones.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.